1. Field of the Invention
The present invention relates to a process of catalytic steam reforming of hydrocarbons having at least 2 carbon atoms per molecule at a temperature in the range of 300.degree.-600.degree. C, and to be more precise, it relates to a process of manufacturing a methane-containing gas -- particularly a methane-rich gas -- by, for instance, adiabatically steam reforming the material hydrocarbon in the presence of an improved catalyst comprising a nickel component and a magnesia component (hereinafter called `a nickel-magnesia catlayst` for short) which is capable of demonstrating superb effects in the low-temperature steam reforming reaction.
2. Description of the Prior Art
There have hitherto been proposed a variety of nickel-containing catalysts for use in low-temperature steam reforming of the feed hydrocarbon. To cite instances, there are Japanese Pat. No. 11047/1965 teaching a catalyst consisting of nickel-alumina-lanthanide rare earth, Japanese Pat. No. 11048/1965 teaching a catalyst consisting of nickel-alumina-iron and Japanese Pat. No. 19174/1970 teaching a catalyst consisting of nickel-alumina-alkaline earth metal.
However, the conventional nickel-containing catalysts -- including the above cited catalysts -- for use in low-temperature steam reforming are not always satisfactory from the view point of the life of catalyst. Especially in the case of serving for the low-temperature steam reforming reaction under the condition of high pressure which has become popular of late, they are incapable of stable retention of their catalytic properties for a long period of time because of deposition of carbonaceous matters thereon and other factors. Moreover, inasmuch as the conventional nickel-containing catalysts are poisoned by a sulfur-containing contaminant, in the case of treating feed hydrocarbons containing relatively much sulfur compounds, it has been required to subject said feed hydrocarbon to a pre-treatment process for desulfurization under severe conditions.